In(mostly military) aircraft, the ejection seat is a system designed to rescue the pilot or other crew in an emergency. In most designs, the seat is propelled out of the aircraft by an explosive charge or rocket motor, carrying the pilot with it. The concept of an ejectable escape capsule has also been tried. Once clear of the aircraft, the ejection seat deploys a parachute, and descends safely to earth.While a bungee-assisted escape from an aircraft took place in 1910, the modern pattern for an ejection seat was invented in Germany in 1938 and perfected during World War II. Prior to this, the only means of escape from an incapacitated aircraft was to jump clear ("bail-out"), and in many cases this was difficult due to injury, the difficulty of egress from a confined space, g-forces, the airflow past the aircraft and other factors.The first ejection seats were developed independently during the World War II by Heinkel and SAAB. Early models were powered by compressed air and the first aircraft to be fitted with such a system was the Heinkel He 280 prototype jet fighter in 1940. One of the He 280 test pilots, Helmut Schenk, became the first person to escape from a stricken aircraft with an ejection seat on January 13, 1942 after his control surfaces iced up and became inoperable.The first operational type to provide ejection seats for the crew was the Heinkel He 219 Uhu night fighter in 1942.In late 1944, the Heinkel He 162 featured a new type of ejection seat, this time fired by an explosive cartridge. In this system the seat rode on wheels set between two pipes running up the back of the cockpit. When lowered into position, caps at the top of the seat fitted over the pipes to close them. Cartridges, basically identical to shotgun shells, were placed in the bottom of the pipes, facing upward. When fired the gases would fill the pipes, "popping" the caps off the end and thereby forcing the seat to ride up the pipes on its wheels, and out of the aircraft. By the end of the war, the Do-335 Pfeil, Me-262 Schwalbe and Me-163 Komet also were fitted with ejection seat.The purpose of an ejection seat is pilot survival, not pilot comfort. Many pilots have suffered career-ending injuries while using ejection seats, including crushed vertebrae. The pilot typically experiences an acceleration of about 12 to 14 g (117 to 137 m/s²). Western seats usually impose lighter loads on the pilots; 1960s-70s era ex-Soviet technology often goes up to 20-22 g (with SM-1 and KM-1 gunbarrel type ejection seats). Career-ending injuries are quite common, partly because eastern military pilots usually continue to fly into their late 40s or early 50s and end (retire) their flying career afterward, while most western jet pilots retire from the military in their late 30s.Lt. William Belden ejects from an A-4 Skyhawk on the deck of the Shangri-La.
Lt. William Belden ejects from an A-4 Skyhawk on the deck of the Shangri-La.The Russian K-36 ejector seat manufactured by NPP Zvezda is considered by many as the world's most advanced. It was studied at length by the US Navy and Airforce and IBP Aircraft opened up a factory in the US to manufacture it for the F-22 Raptor and the Joint Strike Fighter. The US Government however selected the Martin Baker seat from the UK in a political move for the new US fighters. The amazing capabilities of the K-36 were convincingly demonstrated at the Fairford Air Show on 24 July 1993 when the pilots of two MiG 29 fighters successfully ejected after a mid-air collision.By May 2006, Martin-Baker ejection seats had saved 7196 lives.The "standard" ejection system operates in two stages. First, the entire canopy or hatch above the aviator is opened or jettisoned, and the seat and occupant are launched through the opening. In most earlier aircraft this required two separate actions by the aviator, while later egress system designs, such as the Advanced Concept Ejection Seat model 2 (ACES II) will perform both functions on a single action.The ACES II ejection seat is used in most of the United States Air Force's mainline fighters, including the A-10, F-15, and F-16. The A-10 uses connected firing handles that activate both the canopy jettison systems, followed by the seat ejection. The F-15 has the same connected system as the A-10 Seat. Both handles accomplish the same task, so pulling either one suffices. The F-16 has only one rubber handle located between the pilot's knees, since the cockpit is too narrow for side-mounted handles. Unlike the F-15 and A-10, however, the F-16 does NOT have canopy breaking systems installed. The angle of the ejection seat inside the aircraft is so extreme that a pilot's head would strike the canopy before any installed canopy breakers would. Also, the canopy is constructed of highly durable composite material which cannot be shattered by seat ejection.
Tags: Ejection Seat test Military jet aircraft Boeing Eads Lockheed Martin Sukhoi Mig F-22 T-50 F-18 Mig-29 Su-35 A380 747 78
